1. Field of the Invention
This invention relates generally to food cooking appliances and more particularly to an automated food cooking appliance which is most advantageous for assisting in the preparation of safe, uniform and high quality food products in high volume restaurants although using moderately trained operators.
2. Description of the Related Art
Cooking appliances have developed over many millennia for assisting the cooking of food products for human consumption. In the last century, automated features have been added, particularly for controlling the cooking temperature and for signaling the cooking time. Cooking temperatures have long been controlled by closed loop feedback control systems which include a temperature sensor and a relay or a solenoid controlled valve for controlling electric or gas fueled heaters. Feedback control systems are commonly implemented in both analog and digital circuits. The development of the electronic computer and microcontrollers, which are special purpose computers for controlling a particular apparatus, has made possible the implementation of control systems under the control of computer software.
The past half century has seen the development of numerous chains of high volume, rapid service, specialty restaurants. Such restaurants are characterized by a specialized menu of prepared food products having a quality which is uniform throughout the chain. This uniformity of quality reassures customers that they will receive the same high quality products at any restaurant in the chain. Reputable restaurants are also quite concerned about the maintenance of safe health standards because even a single problem can cause extensive damage to their reputation.
In order to make the food products available at an affordable price, such restaurants ordinarily employ large numbers of employees who are not highly trained in food preparation. Therefore, in order to maintain high standards of safety, quality and uniformity, it is desirable that the cooking procedures be closely controlled by the responsible, central authority, typically a franchisor. Maintenance of food sanitation and safety and compliance with health regulations are important reasons that cooking and other aspects of food preparation be controlled by the franchisor.
One way of controlling the food preparation procedures so they are uniformly practiced in the best manner is to automate the procedures. Consequently, the prior art has seen temperature controls and the use of independent timer systems which signal the elapse of a timing cycle for a cooking procedure, such as the frying of french fries. However, the audible signals or the computer screen displays generated by the completion of such a timing cycle are typically not closely physically associated with the equipment upon which the cooking procedure is being performed. For example, a computer display may be located above or beside an appliance and often above a group of appliances.
A grill is one of the most common cooking appliances, particularly in restaurants of the type described. A grill is often the cooking appliance upon which the most featured product of the restaurant is prepared, such as a hamburger, for a restaurant known for its unique or featured hamburgers. Modem grills have automated temperature controls and are also used with independent timing and signaling systems. Grills are also known which, after the operator places food products on the grill and depresses a button, the grill automatically lowers an upper platen upon the food products, initiates a timing cycle and automatically raises the upper platen when a stored cooking time has elapsed. From a control perspective, such a system is not unlike a conventional electric toaster into which a piece of bread is placed, an actuating handle is depressed to lower the bread into the cooking zone and, after a timing interval, the bread is automatically raised to a position out of the cooking zone for removal by the operator. These systems control a single food heating operation at a single location on the grill.
Food products heated on grills, however, often require a series of related heating and manipulative operations which must be coordinated, each with its own timing requirements and therefore its own opportunities for error. For example, after a food product is properly cooked, if it is not served immediately, it must be held on the grill so that it will remain hot and moist. This holding operation is also referring to as staging. Because each customer expects the rapid service for which the restaurant is known, and because there are large fluctuations in the rate of customer orders during a typical day, the cooking process often must be initiated in advance of customer orders and the rate of serving varies and can be unpredictable. Therefore, a major part of the grill operation is commonly devoted to the proper holding of the cooked food products. However, in order to maintain quality and freshness, the held food products must not be held too long and, when the holding time standard of the operator or franchiser has been exceeded, the food products must be diverted to other uses or discarded.
Prior art systems do not have control systems which are integrated with multiple zones on the grill and are capable of controlling the entire series of food product heating and physical manipulation from placement of the food product on the grill through its removal from the grill. As a result, either at least some of the operations on the grill are left entirely to the knowledge of and timely action by the operator, or, if a separate timing and display system is used, its signals and displays must be interpreted by the operator requiring the operator to know the place the operations are to be performed. Additionally, after a timer has signaled the elapse of a time interval, there is commonly no way to signal that a manual operation has actually been performed by the employee. Therefore, if an employee fails to take an action, fails to take the action at the proper location or fails to take the action within the appropriate time after the action is supposed to be performed, food product quality and possibly food safety can be reduced. Thus, with prior art systems there are excessive opportunities for human errors and resulting departures from the preparation of food products of optimum quality and safety.
It is therefore an object and feature of the invention to provide a grill which not only automatically controls the grill itself, but also controls the interaction of the grill with the operator who performs manual operations on the food products on the grill.
A further object and feature of the invention is to provide a grill control system which has a computer control which controls the interaction of the human operator with the grill to establish control over not only the entire cooking process but also any subsequent holding, serving and diversion to chili operations which may be associated, for example, with the preparation of hamburgers. The control and the cooking equipment are integrated to control performance of the cooking process. Control of cooking and holding (staging) occurs and the work product is tracked beginning from entry of raw food work product onto the grill all the way through removal of the work product for assembly into a sandwich or diversion to holding for subsequent chili preparation.